Apparatus for controlling the operation of an ice making machine



A ril 26, 1966 c. 1. BUSSELL 3,247,677

APPARATUS FOR CONTROLLING THE OPERATION OF AN ICE MAKING MACHINE Filed Jan. 23, 1964 2 Sheets-Sheet 1 INVENTOR 12 Clarence I. Bussell Wag;

ATTORNEY April 1966 c. 1. BUSSELL 3,247,677

APPARATUS FOR CONTROLLING THE OPERATION OF AN ICE MAKING MACHINE Filed Jan. 23, 1964 2 Sheets-Sheet 2 INVENTOR Clarence I. Bussell ATTORNEY United States Patent 3,247,677 APPARATUS FOR CONTROLLING THE OPERA- TIGN OF AN ICE MAKING MACHINE Clarence I. Russell, 6439 Mobud, Houston, Tex. Filed Jan. 23, 1964, Ser. No. 339,777 13 Claims. (Cl. 62138) A demand exists for a small, relatively inexpensive ice making machine which provides ice in a conveniently ready to use form such as cubes or small chunks. It is common for such machines to be located in resort areas for the purpose of supplying the needs of fishermen and other vacationers. Restaurants and clubs alsorequire such a machine.

Several different types of ice making machines are presently available for satisfying this demand. In general, they utilize a co-axial type structure for forming the ice. In this co-axial type structure, a tubular member is provided through which water is pumped. The tubular member is surrounded by a sleeve through which a suitable refrigerant, such as Freon, is pumped. If the refrigerant is cooled to a temperature below the freezing point of water before it is admitted into the sleeve, ice will form on the inner surface of the tubular member. Thereafter, the ice will thicken as water is pumped through the tube, reducing the effective diameter of the tubular member. After the ice attains a predetermined thickness, usually determined by the size of the hole remaining, the heat exchanger and expansion valve utilized for cooling the refrigerant is by-passed, allowing hot refrigerant to flow through the sleeve. The hot refrigerant will melt that portion of the ice immediately adjacent the Wall of the tubular member, allowing the water pressure to force the ice from the tubular member.

In using such a machine, it is desirable that the ice be as thick as practicable, but it is extremely important that the freezing operation be stopped prior to the time that the tubular member freezes solid in order that rupture of the-tubular member may be prevented. If the tubular member ruptures, the refrigerant contained within the system will escape. In addition, water will usually enter the cooling system, damaging the compressor and other parts of the cooling system. As such ice making machines are normally located at points where they are unattended or only attended by unskilled personnel, it is extremely desirable that the means provided for controlling the flow of hot and cooled refrigerant through the system be reliable in order that a supply of ice may always be available to the customers and to prevent damage to the equipment which may result in extremely expensive repair bills.

In accordance with the principles of the present invention, an inexpensive but extremely reliable method and apparatus is provided for controlling the operation of an ice making machine. In practicing the present invention, the amount of water flowing from the tubular member is utilized to provide a determination of the state of freezing or manufacture of the ice. Means effective responsive to the amount of water flowing from the tubular member, being less than a predetermined amount, are provided for actuating a by-pass means to prevent further freezing.

In accordance with the preferred embodiment of the invention described herein, a water cabinet having a float is provided. A slot is formed in the water cabinet, the amount of water discharged through the slot being related to the volume of water that will pass through the tube when the desired degree of freezing has been attained. So long as the water passing through the tube is greater than a predetermined amount, the position of the float will be above a predetermined level, causing a micro-switch which controls a solenoid operated by-pass valve to be closed, thereby maintaining the solenoid 0perated by-pass valve in a closed position. At such time as the amount of water flowing from the tubular member becomes less than that discharged through the slot provided in the water cabinet, the level of the water in the water cabinet will fall. As the water falls below a predetermined level, the float will also fall, opening the micro-switch which controls the solenoid operated valve in the by-pass line. The solenoid operated bypass valve will therefore open, permitting a major portion of the hot refrigerant to pass directly in contact with the cooling tubes.

A system as described above is operable if the total discharge capacity of the Water disiharge openings formed in the water cabinet is equal to the rate of flow of water from the tubular member when the desired thickness of ice is obtained. However, any variation in the discharge capacity of the discharge openings is immediately reflected by a change in thickness of the ice formed.

For more reliable operation, it is preferred that baffle means be provided for diverting the flow of water away from the water cabinet when the flow of water through the tubular member falls below a predetermined rate.

If the flow of water from the tubular member to the water cabinet is diverted, a substantial change in the discharge capacities of the discharge openings formed in the water cabinet can occur without greatly affecting the operation of the control, since even a small drop in water level will cause the switch which controls the bypass valve to open.

The preferred means for diverting the flow of water front the tubular member to the water cabinet is an adjustable ibaflle.

It is known that if water is applied to a long tube of relatively constant, restricted cross sectional area at a constant pressure, the distance the water will travel after discharge from the tube is directly related to the cross sectional area of the tube and the rate of flow of the water. It is, therefore, possible to obtain an indication of the diameter of the hole contained within the tube of ice by determining the distance the water travels after discharge from the tubular member. The position of this baffle. plate is adjusted such that when the ice within the tubular member forms to the desired thickness, the bafl le plate will prevent the water flowing into the container, permitting the float to fall and open the thy-pass line. If the ice is less than the desired thickness the flow rate of the water will be such that the stream of water will pass over the baffle plate. Excellent results i are achieved in that the size of the holes formed in the container is not nearly so critical and the operation of the system is not disrupted by one or more of the holes being plugged or clogged to the extent that it would be true if only the size of the holes is used to control the level of water in the water cabinet.

Many objects and advantages of the present invention will become apparent to those skilled in the art'as the following detailed description unfolds when taken in conjunction with the appended drawings wherein like referenced numerals denote like parts and in which:

FIGURE 1 is a perspective View illustrating the principles of an ice making machine provided. by the present invention;

FIGURE 2 is a view in cross section taken along line 22 of FIGURE 1;

FIGURE 3 is a cross sectional view taken along line 3-3 of FIGURE 1;

FIGURE 4 is a fragmentary view, partially in cross section, illustrating the manner in which a substantially solid plug of ice may be formed at the entrance of the ice making portion of the tubular member to expedite the removal of ice from the tube at the completion of the ice forming cycle; and- FIGURE 5 illustrates means for breaking the column of ice formed into small pieces suitable for use.

Turning now to FIGURE 1 of the drawings, the ice making machine provided by the present invention is denoted generally by the reference numeral 10. It is seen to comprise a co-axial cooling coil 12 which comprises a tubular member 14 surrounded along a portion of its length by a sleeve 16. As shown, the ends 18 and 20 of the sleeve 16 are sealed to the tubular member at the entrance and exit of the ice making zone. providing an enclosed area 17 into which a conventional refrigerant such as Freon may be circulated.

One end of the enclosed area defined between the tubular member 14 and the sleeve 16 is connected by tubing 22 to a compressor 24, which is suitably driven by a motor 26. The output of the compressor 24 is connected by tubing 28 to the input of a heat exchanger 30 which may be cooled by a motor driven fan 32. The output of the heat exchanger 30 is connected through tubing 32 to an expansion valve 34 of the type that is conventional in the refrigeration field. Thus, the refrigerant contained within the sealed system is compressed, forming a liquid, by the compressor 24. The refrigerant will absorb energy in the process of being converted from the normally gaseous state to a liquid state and the liquid Freon produced by the compressor 24 will be at a substantially elevated temperature. As the liquid Freon passes through the heat exchanger 30, it will lose a great deal of its heat and upon passing through the expansion valve 34, it will again assume the gaseous state. The refrigerant will lose thermal energy as it is converted from a liquid to a vapor, causing the temperature of the gaseous refrigerant admitted into the enclosed area 17 to be substantially below the freezing point of water.

The tank 38 provides a supply of water for the system. To this end, the tank 38 may be supplied with make up water through pipe 40 from any convenient water supply. A float valve 42 such as is well known may suitably be used for controlling the level of Water within the tank 38 to assure that an ample supply of water will always be available. The tank 38 is connected by a pipe 44 to a pump 46 which may be driven by a motor 48. The output of pump 46 is connected by pipe 50 to the tubular member 14 as shown.

The pipe 50 is also connected by a by-pass line 52 and a pressure sensitive valve 54 to the tank 38. The pressure valve 54 is adjusted to maintain a predetermined pressure of the input of the tube 14. At pressures in excess of the predetermined pressure, the valve 54 will open, allowing a portion of the water pumpedby the pump 46 to flow through the by-pass line 52 back to the tank 38.

As the water is pumped through the tube 14, ice will form due to the cooling provided by the refrigerant. As the tube 14 is in intimate thermal contact with the refrigerant, it will be quite cold, causing ice to form on the inner walls of the tube 14. The thickness of the ice formed on the wall of the tube 14 will progressively increase, decreasing the effective cross sectional area of the tube 14 through which the water flows.

A water cabinet 54 is also provided. The water cabinet 54 is preferably divided into compartments 56 and 58 by a divider 60. The divider 60 stops short of the bottom of the cabinet 54, allowing communication between the compartments 56 and 58. The water flowing through the tube 14 empties into the compartment 58, filling the cabinet 54. As the area of communication between the compartments 56 and 58 provided underneath the partition -60 is relatively large, the compartments 56 and 58 will fill at substantially the same rate. One side of the compartment 56 is cut away to form a slot 62, permitting water flowing into the cabinet 54 to flow into the tank 38. The compartment 56 is also suitably provided with two groups of holes 64A and 64B. Water passing from the compartment 56 through the holes 64 is also discharged into the tank 38.

Also positioned within the compartment 56 is a buoyant globe or ball 66. So long as the amount of water passing from the member 14 is greater than the amount of water discharged from the compartment 56 into the tank 38 through the slot 62 and the holes 64, the ball 66 will be at or rising toward its maximum level, as established by the slot 62 of the compartment 56. The maximum level will suitably be at approximately the midway point of the slot.

When the ball 66 is above a predetermined level, suitably inch above the bottom of the slot, it will contact the arm 68, causing the micro-switch 70 to be closed. As long as the micro-switch 70 is closed, the solenoid operated valve 72 will also remain in its closed position. At such time as the thickness of the ice formed within the tube 14 attains a desired thickness, the tube 14 will be constricted to the extent that the amount of water emptying into the cabinet 54 will become less than that discharged into the tank 38 through slot 62 and holes 64. The level of the float 66 will, therefore, drop below the predetermined level, allowing the micro-switch to open and causing the solenoid operated valve 72 to also open.

The water level in the compartments 56 and 58 will continue to fall as water is discharged from the holes 64. When the water reaches the level of holes 64A, the rate at which it falls will decrease, however. It is desirable that the water level be reduced to that set by the group of holes 64A during the defrost cycle to insure that Water released as the ice is removed does not cause the water level to rise suificiently to close the micro-switch 70 prior to completion of the defrost cycle.

As the valve 72 opens, the hot refrigerant will flow through the line 74, the solenoid operated valve 72, line 76 and line 36 into the enclosed area 17. The hot refrigerant flowing through the sleeve 16 is effective to prevent further freezing and produce a molten or liquid inner face between the ice and the tube 14, allowing the water pressure produced by the pump 46 to force the ice from the tube 14.

An additional safety feature comprising a micro-switch 78 operated by a linkage 80 is provided. Thus, in the event the solenoid operated valve 72 does not open, as the level of the water in the cabinet 54 and the level of the ball 66 to the level of holes 64B fall, the ball 66 will bear against the linkage 80 and open the micro-switch 78. As the micro-switch 78 opens, it removes power from the compressor 24. A short time later, depending upon the ambient temperature, suflicient defrosting will occur to allow the ice formed within the tube 14 to freeitself from the tube 14, permitting the water provided by pump 46 to force the ice from the tube 14. Thus, the system will be disabled if at any time the tube 14 is blocked or if water is not available for freezing.

It will be appreciated that a certain amount of pressure is lost by Water flowing through the opening remaining in the ice and that the removal of ice from the tube would be expedited if that portion of the ice at the entrance of the ice making zone were completely solid. In accordance with the present invention, a sleeve 32 (FIG- URE 4), suitably in the order of 12 inches long, is provided at the entrance 80 of the ice making zone of tubular member 14.

Due to the reduced cross sectional area, the opening in the ice formed within the sleeve 32 will be somewhat less than the opening present in the ice formed throughout the balance of the tube. However, in view of the rather short length of the sleeve 82, the smaller opening within the ice contained within the sleeve provides a nozzle effect rather than adversely affecting the amount of flow and pressure of the water throughout the length of the tube 14. It will be appreciated that as the size of the opening remaining gets smaller and smaller, it tends to decrease in size at an increase in rate due to the smaller volume of ice required to reduce its size. It is, therefore, quite common for the length of ice formed within the sleeve to freeze solid in the interval of time that elapses between the time at which the ice attains the desired thickness and the time at which the level of the ball contained within the compartment 56 drops suflrciently to open the switch 7 which controls valve 72. Thus, the pressure produced by the pump 46 may act against a solid or very nearly solid cylinder of ice 73, greatly increasing the eflficiency with which the ice is removed from the tubular member 14.

As also mentioned earlier, it is desirable that the ice be provided in sizes that are convenient for use. To this end, an angle fitting 84, similar to that shown in FIG- URE whose inside diameter is somewhat larger than the inside diameter of the tube 14, is attached to the exit end 84 of the tube 14. As the ice 88 is pushed from the tube 14, it will bear against the inner surface of the angle fitting, causing it to break into lengths 90.

The lengths 90 of ice are supported and guided by rods 92 upon leaving the tubular member 14. As the pressure of the water causes additional lengths 90 of ice to break from the main body of ice 88, the pieces of ice slide along the rods 92 and fall into the bin 94 where they are stored until used. Any water flowing from the tubular member 14 passes freely between the rods 92.

The example of the invention described above is adequate for many applications. However, it is desirable that the defrost cycle begin as soon as possible after the desired thickness of ice is formed. As mentioned previously, ice machines of this type are frequently located in unattended areas and reliability of operation is extremely important to prevent damage to the system.

As best seen in FIGURES 2 and 3 of the drawings, the box 96 into which the tube 14 empties and which directs the water into the compartment 58 is provided with a movable baffle 98. Positioned between the baffle 98 and the back of the box 96 is an opening 100 which discharges into the tank 38. The horizontal distance the stream of water travels before it reaches the top of the baffle 98 is a function of the amount of liquid flowingthrough the tube 14. In this connection, it will be appreciated that due to the long length of the tube 14, the restriction of thecross sectional area does not operate to produce a spray or high pressure stream but rather, due to the resistance of the flow through the ice, the water will be discharged from the tube .14 at a relatively low pressure.

The baffle 98 is adjusted such that when the opening in the ice is greater than that desired, the water will pass over the baffle 98 and into the cabinet 54, maintaining the solenoid operated valve 72 closed. Ice will continue to be formed within the tube 14 so long as the bypass valve 72 is closed. At such time as the thickness of ice attains a desired level, the amount of water flowing will be reduced to the point that the stream of water discharged from the tube 14 will strike the baffle 84 and be discharged through the opening 100 directly into the tank 38. The level of water contained within the cabinet 54 will then fall very rapidly as it is discharged from slot 62 and holes 64, causing the micro-switch 70 to open and in turn opening the solenoid operated valve 72.

From the above, it is seen that the operation of the invention, when equipped with the baffle 98 or other means suitable for diverting the flow of water, is not dependent upon, a critical amount of water being discharged through the slot 62 and the holes 64, it only being necessary that the discharge openings 62 and 64 allow a sufficient amount of water to be discharged from the cabinet 54 into the tank 38 to allow the micro-switch 70 to open prior to the time that the ice contained within the tube 14 becomes sufiiciently solid to produce damage. It will also be apparent that the adjustment is quite simple to make and,

6 accordingly, can be performed by personnel of a very low skill level.

The level of water in the cabinet 54 will remain below the predetermined level so long as the amount of water discharged through the holes 62 and slot 62 is greater than the amount of water flowing into the cabinet. Thus, the by-pass valve 72 will be open at all times when the ice is formed to the desired thickness, as indicated by the flow of water from the tubular member 14 to the water cabinet 54 being less than that discharged through the discharge openings 62 and 64. When all the ice is forced from the tubular member 14, the volume of water flowing from the tubular member 14 increases sharply, causing the level of water in the cabinet 54 to rise. The valve 72 is closed when the water in the cabinet 54 reaches the predetermined level, causing the refrigerant to pass through the heat exchanger 30 and expansion valve 34. However, since the water level will fall below the base of slot 62, a time delay in clearing the valve 72 is provided, insuring that all of the ice is removed from tube 14 prior to initiation of the next freezing cycle. The next freezing cycle will then continue until the ice forms to the desired thickness, at which time the valve 72 will again open responsive to the drop in the water level of cabinet 54.

The apparatus provided by the present invention is extremely reliable in that any time the volume of water flowing through the tube 14 falls below the predetermined level, indicating that the desired amount of ice is formed, the float will fall, opening the solenoid operated valve '72. If at any time the water level falls below a second predetermined level, indicating a malfunction of the system, power is removed from the compressor motor 26. I

The system is largely fail safe in that if a leak should be produced in the ball 66, it will sink, disabling the compressor 24 and preventing damage to the system. For this reason, the present invention is deemed superior to the present day ice making machines which rely upon vollume or pressure meters for achieving the desired contro Although the invention has been described with refer ence to particular embodiments, many changes and modifications will become obvious to those skilled in the art in view of the above description. For example, separate floats could be attached to the linkages 68 and for operating the micro-switches responsive to the water attaining predetermined levels. The invention is, therefore, to be limited only as necessitated by the scope of the appended claims and not to what is specifically described herein.

What I claim is:

1. An ice making machine of the class having a tubular member of substantially constant cross section, means for pumping water through said tubular member, means for circulating a refrigerant in contact with an ice making zone of said tubular member, cooling means for reducing the temperature of said refrigerant below the freezing point of water whereby circulation of said cooled refrigerant in contact with the tubular member will form ice within said ice making zone of said tubular member and bypass means for bypassing the cooling means when it is desired to subject said tubular member to refrigerant at a temperature in excess of the freezing point of water to free the ice formed within the ice making zone of said tubular member from said tubular member that comprises a water cabinet for receiving water flowing from said tubular member, first switch means effective responsive to the water in said water cabinet being less than a first predetermined level for actuating said bypass means, said watercabinet including at least one opening positioned below said first predetermined level for discharging water from said water cabinet at a rate greater than the rate of flow of water into said water cabinet from said tubular member after ice is formed to the desired thickness in said tubular member, and means .for preventing the flow of water from said tubular member to said water cabinet responsive to the flow rate of water from said tubular member being less than a predetermined amount.

2. An ice making machine as defined in claim 1 fur- .ther including additional switch means effective responsive to the water in said water cabinet being less than a second predetermined level for disabling said means for circulating.

3. An ice making machine of the class having a tubular member of substantially constant cross section, means for pumping water through said tubular member, means for circulating a refrigerant in contact with an ice making zone of said tubular member,'cooling means for reducing the temperature of said refrigerant below the freezing point of water whereby circulation of said cooled refrigerant in contact with the tubular member will form ice within said ice making zone of said tubular member and bypass means for bypassing the cooling means when it is desired to subject said tubular member to refrigerant at a temperature in excess of the freezing point of water to free the ice formed within the ice making zone of said tubular member from said tubular member that comprises a water cabinet for receiving water flowing from said tubular member, first switch means effective responsive to the water in said water cabinet being less than a first predetermined level for actuating said bypass means, said water cabinet including at least one opening positioned below said first predetermined level for discharging water from said water cabinet at a rate greater than the rate of fiow of water into said water cabinet from said tubular member after ice is formed to the desired thickness in said tubular member, and means for preventing the flow of Water from said tubular member to said water cabinet responsive to the flow rate of water from said tubular member being less than a predetermined amount, said tubular member including an elongated region of restricted cross sectional area at the entrance to the ice making zone. I

4. An ice making machine as defined in claim 3 wherein said region is of increased wall thickness.

5. An ice making'machine as defined in claim 4 wherein said region of restricted cross sectional area is characterized by being of greater wall thickness.

6. In an ice making machine including an ice making zone of co-axial construction, the ice making zone defining a tubular member open at both ends to permit the fiow of Water and a sleeve sealed to the tubular member to form an enclosed area that is part of a sealed system containing the refrigerant, means for pumping Water through said tubular menrber, means for pumping the refrigerant throughthe sealed system including the enclosed area, heat exchange means and expansion valve means for cooling said refrigerant to a temperature below the freezing point of water and by-pass means for bypassing said heat exchange means and said expansion valve means responsive to the ice formed in said tubular member attaining a predetermined, desired thickness; the combination with said bypass means of a water cabinet into which the water flowing from said tubular member empties, a buoyant member for closing a switch responsive to the level of water in the water cabinet attaining a predetermined level, said bypass means being closed when said switch is closed and in the open condition when said switch is open, said water cabinet including at least one opening positioned at a level below the said predetermined level of said water for discharging water from said cabinet at a rate related to the discharge rate of water from said tubular member and means for diverting the water discharged from said tubular member away from said water cabinet responsive to the water being discharged from said tubular member at a rate indicative of the desired thickness of ice having formed in said tubular member.

7. An ice making machine as defined in claim 6 wherein said switch includes lever means extending over said water cabinet whereby said buoyant member raises said lever to close said switch responsive to the level of water in said water cabinet attaining said predetermined level. 8. An ice making machine as defined in claim 7 where in said water cabinet includes a first compartment communicating with 'a second compartment at a point below said at least one opening, said first compartment containing said buoyant member and wherein the water flowing from said tubular member empties into said second compartment.

9. An ice making machine as defined in claim 8 wherein said tubular member includes an elongated region of restricted cross sectional area, formed in the inlet side of the ice making zone of said tubular member.

10. An ice making machine of the class having a' tubular member of substantially constant cross section, means for pumping water through said tubular member, means for circulating a refrigerant in contact with an ice making zone of said tubular member, cooling means for reducing the temperature of said refrigerant below the freezing point of water whereby circulation of said cooled refrigerant in contact with the tubular member will form ice within said ice making zone of said tubular member and bypass means for bypassing the cooling means when -it is desired to subject said tubular member to refrigerant at a temperature in excess of the freezing point of water to free the ice formed within the ice making zone of said tubular member from said tubular member that comprises a water cabinet for receiving water flowing from said tubular member, first switch means effective responsive to the water in said water cabinet being less than a first predetermined level for actuating said bypass means, additional switch means effective responsive to the water in said water cabinet being less than a second predetermined level for disabling said means for circulating, said water cabinet including at least one opening positioned below said first predetermined level for discharging water from said water cabinet at a rate greater than the rate of flow of water into said water cabinet from said tubular member after ice is formed to the desired thickness in said tubular member, and means for preventing the flow of water from said tubular member to said water cabinet responsive to the flow rate of water from said tubular member being less than a predetermined amount.

11. An ice making machine as defined in claim 10 wherein said buoyant member is a free floating ball.

12. An ice making machine as defined in claim 10 wherein said water cabinet includes a vertically disposed bafiie member separating said water cabinet into a first compartment containing said first mentioned switch, said additional switch means and said buoyant member, said baffle means terminating short of the bottom of said water cabinet whereby Water emptying into the other of said compartments from said tubular member will flow into a first of said compartments at a rate to maintain the water level in said two compartments substantially constant.

13. An ice making machine of the class having a tubular member of substantially constant cross section, means for pumping water through said tubular member, means for circulating a refrigerant in contact with an ice making zone of said tubular member, cooling means for reducing the temperature of said refrigerant below the freezing point of water whereby circulation of said cooled refrigerant in contact with the tubular member will form ice within said ice making zone of said tubular member, and bypass means for bypassing the cooling means when it is desired to subject said tubular member to refrigerant at a temperature in excess of the freezing point of water to free the ice formed within the ice making zone of said tubular member from said tubular member that comprises a water cabinet for receiving water flowing from said tubular member, first switch means effective responsive to the water in said water cabinet being less than a first predetermined level for actuating said bypass means, said water cabinet including at least one opening positioned geezer? below said first predetermined level for discharging water from said water cabinet at a rate greater than the rate of flow of water into said Water cabinet from said tubular member after ice is formed to the desired thickness in said tubular member, and means for preventing the flow of water from said tubular member to said water cabinet responsive to the flow rate of water from said tubular member being less than a predetermined amount, said last named means comprising an upstanding baflle member adapted to be positioned with its upper edge at different positions relative to a stream of Water flowing from said tubular member.

References Cited by the Examiner UNITED STATES PATENTS Gamble 73-215 Watt et al. 6 2--352 X Batteiger 62-138 Lee 62--73 Council et a1 62352 X ROBERT A. OLEARY, Primary Examiner. 

1. AN ICE MAKING MACHINE OF THE CLASS HAVING A TUBULAR MEMBER OF SUBSTANTIALLY CONSTANT CROSS SECTION, MEANS FOR PUMPING WATER THROUGH SAID TUBULAR MEMBER, MEANS FOR CIRCULATING A REFRIGERANT IN CONTACT WITH AN ICE MAKING ZONE OF SAID TUBULAR MEMBER, COOLING MEANS FOR REDUCING THE TEMPERATURE OF SAID REFRIGERANT BELOW THE FREEZING POINT WATER WHEREBY CIRCULATION OF SAID COOLED REFRIGERANT IN CONTACT WITH THE TUBULAR MEMBER FORM ICE WITHIN SAID ICE MAKING ZONE OF SAID TUBULAR MEMBER AND BYPASS MEANS FOR BYPASSING THE COOLING MEANS WHEN IT IS DESIRED TO SUBJECT SAID TUBULAR MEMBER TO REFRIGERANT AT A TEMPERATURE IN EXCESS OF THE FREEZING POINT OF WATER TO FREE THE ICE FORMED WITHIN THE ICE MAKING ZONE OF SAID TUBULAR MEMBER FROM SAID TUBULAR MEMBER THAT COMPRISES A WATER CABINET FOR RECEIVING WATER FLOWING FROM SAID TUBULAR MEMBER, FIRST SWITCH MEANS EFFECTIVE RESPONSIVE TO THE WATER IN SAID WATER CABINET BEING LESS THAN A FIRST PREDETERMINED LEVEL FOR ACTUATING SAID BYPASS MEANS, SAID WATER CABINET INCLUDING AT LEAST ONE OPENING POSITIONED BELOW SAID FIRST PREDETERMIND LEVEL FOR DISCHARGING WATER FROM SAID WATER CABINET AT A RATE GREATER THAN THE RATE OF FLOW OF WATER INTO WATER CABINET FROM SAID 